Cervical cancer screening: Risk assessment, evaluation, and management after screening

INTRODUCTION — Screening for cervical cancer and its precursors includes assessing cervical cytology and/or testing for oncogenic subtypes of human papillomavirus (HPV). In patients with abnormal cervical cancer screening results, follow-up with colposcopy and cervical biopsies may result in a diagnosis of cervical intraepithelial neoplasia (CIN) or cervical cancer.

Management of cervical cytology and HPV results are reviewed here.

Other issues related to cervical cancer screening are discussed separately:

●Cervical cancer screening (see "Screening for cervical cancer in resource-rich settings" and "Cervical cancer screening tests: Techniques for cervical cytology and human papillomavirus testing")

●Interpretation of the cytology/HPV report; this includes management of specimens that have an absent endocervical cell/transformation zone, are unsatisfactory for evaluation, or contain benign-endometrial cells (see "Cervical cancer screening: The cytology and human papillomavirus report")

●Screening results that demonstrate glandular lesions (see "Cervical cytology: Evaluation of atypical and malignant glandular cells")

●CIN (see "Cervical intraepithelial neoplasia: Management")

TERMINOLOGY —  (table 1)

●Negative for intraepithelial malignancy (NILM) – A specimen that is adequate for evaluation and in which no epithelial abnormality is identified. (See "Cervical cancer screening: The cytology and human papillomavirus report", section on 'Satisfactory for evaluation'.)

●Atypical squamous cells of undetermined significance (ASC-US) – Cells that display abnormalities more marked than simple reactive changes but do not display a squamous intraepithelial lesion; in some cases, these lesions are associated with cervical intraepithelial neoplasia (CIN) [1].

●Atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion (ASC-H) – Cells that likely consist of a mixture of true high-grade squamous intraepithelial lesion (SIL) and other findings that mimic such lesions [1].

●Low-grade squamous intraepithelial lesions (LSIL) – Lesions associated with human papillomavirus (HPV) infection. These tend to be associated with transient changes that regress over time [1].

●High-grade squamous intraepithelial lesions (HSIL) – Lesions associated with high-risk types of HPV (89 to 97 percent in one study [2]) and that have a high risk of progression to CIN or cancer [1].

●Cervical cancer screening co-testing – Testing with both cervical cytology (Pap test) and HPV testing.

●Reflex testing – The collection of a specimen for either HPV or cytology testing, and performing the other test only if the results of the first test are abnormal.

●HPV genotyping – HPV testing refers to a test that is reported positive if any one or more of a set of oncogenic HPV types are detected (table 2). HPV genotyping refers to testing for individual HPV types, usually HPV 16 or 18, but some tests may also include HPV 45 or intermediate-risk HPV types. HPV 16 and 18 are associated with the highest risk of CIN 3 and cancer [3,4]. HPV 45 is associated with approximately 3.7 percent of cervical cancers and has nearly, but not equal to, the risk of HPV 16 or 18 [5]. Only assays approved by a regulatory body (eg, the US Food and Drug Administration [FDA]) should be used for HPV genotyping. (See "Cervical cancer screening tests: Techniques for cervical cytology and human papillomavirus testing", section on 'HPV testing'.)

In 2012, the Lower Anogenital Squamous Terminology (LAST) project of the College of American Pathology and American Society for Colposcopy and Cervical Pathology (ASCCP) published changes in the terminology used to describe HPV-associated squamous lesions of the anogenital tract [6,7]. In the LAST system, histologic cervical findings are described using the same terminology as cytologic findings and are described in the figure (figure 1). However, in this topic, the CIN terminology will be used because that terminology is used in the ASCCP 2019 risk-based management consensus guidelines for abnormal cervical cancer screening tests and cancer precursors. (See "Cervical intraepithelial neoplasia: Terminology, incidence, pathogenesis, and prevention".)

INCIDENCE — A study of 965,360 cervical cytology specimens in patients ages 30 to 64 reported the following distribution of results [8]:

●Negative for intraepithelial lesion or malignancy (NILM) – 96 percent

●Atypical squamous cells of undetermined significance (ASC-US) – 2.8 percent

●Low-grade squamous intraepithelial lesion (LSIL) – 0.97 percent

●High-grade squamous intraepithelial lesion (HSIL) – 0.21 percent

●Atypical glandular cells (AGC) – 0.21 percent

●Atypical squamous cells cannot exclude HSIL (ASC-H) – 0.17 percent

●Squamous cell carcinoma (SCC) – 4.5 per 100,000

However, this study was published in 2013 and thus does not reflect the benefits of HPV vaccination, which began in 2006 for females age 9 to 26 years.

RATIONALE AND RISK ESTIMATION — In 2019, the American Society for Colposcopy and Cervical Pathology (ASCCP), in collaboration with multiple professional societies and government organizations in the United States and Canada, published practice-changing consensus guidelines regarding the evaluation and management of cervical dysplasia [9]. The consensus recommendations are based on the following principles [9]:

●Cervical cancer screening has shifted from primarily testing with cervical cytology to primarily human papillomavirus (HPV)-based testing, as HPV is a more sensitive test for predicting cervical precancers.

●In general, cytology is a marker for current risk of cervical intraepithelial neoplasia (CIN), while oncogenic HPV subtypes are an excellent marker for predicting the presence of current and future risk of CIN.

●Management decisions for patients with abnormal screening results are based on a patient's risk of developing CIN 3+ (CIN 3, adenocarcinoma in situ, and cancer) as this threshold reflects a reasonable balance between cancer prevention and the potential harms of overtesting and overtreatment. For less common results, some studies report a lower threshold of risk (ie, CIN 2+ rather than CIN 3+) so that statistical power can be achieved; clinically, these thresholds are equivalent.

●A patient's risk of developing CIN 3+ is determined by their current HPV and cytology results as well as past screening and clinical history, if known [10]; this is called the patient's "risk estimate." Using risk estimate tables found online and a management guidelines application ("app") both online and for smartphones provided by the ASCCP, a patient's immediate and five-year risk estimates of developing CIN 3+ can be calculated. These risk estimates can be used for any combination of cytology and HPV results, as well as results from prior screening and management.

The risk estimates were derived from a study of approximately 1.5 million patients in the Kaiser Permanente Medical Program, a large health care practice in the United States, who were screened with HPV and cervical cytology and followed for over a decade [10]; the size of this screening population allows for precise risk calculations. These risks were compared with other large cohort studies in the United States of patients who received regular testing with both cervical cytology and HPV testing [11,12].

●The same current screening results may lead to a different management recommendation for one patient versus another patient, depending on past testing results. This idea is carried forward from the previous consensus guidelines, published in 2012, and is referred to as the principle of "equal management for equal risks."

Past HPV history modifies the risk of developing CIN 3+. For example, in an observational study of almost one million patients, one negative HPV result within the past five years compared with no prior HPV result reduced the risk of CIN 3+ at both three and five years by approximately 50 percent (0.04 versus 0.085 percent and 0.06 versus 0.11 percent, respectively) [13]. Similarly, a positive HPV result, especially if recurrent or persistent (defined as consecutively positive HPV results at least 12 months apart), can greatly increase a patient's risk of disease. This is discussed in more detail separately. (See 'Other' below and "Cervical cancer screening: The cytology and human papillomavirus report", section on 'HPV-positive results'.)

On the other hand, prior cytology results alone are not as predictive as HPV in the development of CIN 3+ and are therefore not used to modify subsequent management recommendations [14].

●Once a patient's immediate and five-year risk estimates have been calculated, they are assigned to one of six different clinical action thresholds (algorithm 1). Intervention (treatment or colposcopy) is recommended for those with an immediate CIN 3+ risk ≥4 percent, and surveillance is recommended for those whose risk is <4 percent; the frequency of surveillance depends on the patient's five-year risk for CIN 3+. The six clinical action thresholds are:

•Immediate CIN 3+ risk >60 percent: expedited treatment

•Immediate CIN 3+ risk 25 to 59 percent: expedited treatment or colposcopy

•Immediate CIN 3+ risk 4 to 24 percent: colposcopy

•Immediate CIN 3+ risk <4 percent

-Five-year CIN 3+ risk ≥0.55 percent: surveillance in one year

-Five-year CIN 3+ risk 0.15 to 0.54 percent: surveillance in three years

-Five-year CIN 3+ risk <0.15 percent: surveillance in five years

This is discussed in more detail below. (See 'Management based on risk estimate' below.)

●These guidelines are intended for use in the United States and other high-resource settings. Management may differ in low-resource settings where access to colposcopy, a thorough pathology review, and follow-up capabilities may be limited.

There are many potential combinations of cervical cytology and HPV results, and some of these combinations are not addressed by guidelines. The aim of this topic is to assist clinicians in interpreting the evidence and guidelines and to help the clinician estimate the patient's risk of cancer, even when results do not conform exactly to the set algorithms and risk estimate tables described above. In these situations, the clinician should manage the patient to the highest risk abnormality as this is the safest, most conservative approach.

TABLES AND APPLICATIONS (CALCULATORS) — The American Society for Colposcopy and Cervical Pathology (ASCCP) provides a management guidelines application ("app"), both online and for smartphones, to determine a patient's immediate and five-year risks for developing cervical intraepithelial neoplasia (CIN) 3+. Use of this application allows for the provider to determine the optimal management strategy.

A module that can be embedded into the electronic medical record is being developed but not yet available.

In addition, the risk estimate tables used to determine individual patient risk and management recommendations can be found online.

MANAGEMENT BASED ON RISK ESTIMATE — After using the American Society for Colposcopy and Cervical Pathology (ASCCP) management guidelines application to determine a patient's immediate and five-year risks for developing cervical intraepithelial neoplasia (CIN) 3+ (see 'Tables and applications (calculators)' above), patients are then assigned to one of six different management groups: expedited treatment, a choice between expedited treatment and colposcopy, colposcopy, or surveillance at one-, three-, and five-year intervals (algorithm 1) [9,10].

Intervention: Immediate CIN 3+ risk ≥4 percent

Expedited treatment: Immediate risk >60 percent — Expedited treatment is treatment with excision (usually in the form of loop electrosurgical excisional procedure [LEEP]) without having first performed a colposcopy and is the preferred management option for nonpregnant patients ≥25 years with an immediate risk of CIN 3+ >60 percent. Immediate cervical ablation should not be performed because ablative procedures do not provide a specimen for diagnostic evaluation. (See "Cervical intraepithelial neoplasia: Diagnostic excisional procedures", section on 'Loop electrosurgical excision procedure'.)

Examples — Examples of patients in whom the preferred option is expedited treatment include [9,10]:

●Patients with high-grade squamous intraepithelial lesion (HSIL) who are human papillomavirus (HPV) 16-positive (risk of CIN 3+ 60 percent).

●Under-screened patients (patients with no screening for >5 years) with HSIL who are HPV-positive (risk of CIN 3+ 64 percent).

Expedited treatment is preferred in these patients as colposcopy is unlikely to alter management.

Expedited treatment may also be preferred for patients who are at risk for loss to follow-up or who have completed childbearing [9].

Exceptions

●Expedited treatment is contraindicated in patients <25 years and pregnant patients. (See 'Patients <25 years' below and 'Pregnant patients' below.)

●Patients planning future childbearing, and those in whom the concerns about potential adverse pregnancy outcomes (eg, preterm delivery) after an excisional procedure outweigh concerns about cancer, may reasonably choose colposcopy rather than expedited treatment. Colposcopic biopsies will then provide information to help guide clinical decision-making (eg, treatment with excision or ablation versus follow with observation). This is discussed in detail separately. (See "Reproductive effects of cervical excisional and ablative procedures" and "Cervical intraepithelial neoplasia: Management".)

In all instances, a thorough discussion is required between the provider and patient to discuss the risks and benefits of this treatment option.

Expedited treatment or colposcopy: Immediate risk 25 to 59 percent — Expedited treatment or colposcopy are acceptable options for nonpregnant patients ≥25 years with an immediate risk of CIN 3+ between 25 and 59 percent.

Examples — Three examples of patients (with an unknown screening history) who should undergo expedited treatment or colposcopy include [9,10]:

●HPV-positive with HSIL (risk of CIN 3+ 49 percent)

●HPV-positive with atypical squamous cells cannot exclude HSIL (ASC-H; risk of CIN 3+ 26 percent)

●HPV-negative with HSIL (risk of CIN 3+ 25 percent)

How to choose — As above, expedited treatment is contraindicated in patients <25 years old and pregnant patients and may be avoided in patients whose concerns about potential adverse pregnancy outcomes (eg, preterm delivery) after an excisional procedure outweigh their concerns about cancer. In addition, expedited treatment may be a preferred option for patients who are at risk for loss to follow-up or who have completed childbearing. (See 'Exceptions' above.)

Both excision with LEEP and colposcopy are discussed in detail separately. (See "Cervical intraepithelial neoplasia: Diagnostic excisional procedures", section on 'Loop electrosurgical excision procedure' and "Colposcopy".)

Colposcopy: Immediate risk 4 to 24 percent — For nonpregnant patients ≥25 years old with an immediate risk of CIN 3+ between 4 and 24 percent, colposcopy is the preferred management option. Treatment with excision may be avoided in those patients in whom colposcopic biopsies demonstrate CIN 2 or less.

Examples — Examples of patients with an immediate CIN 3+ risk of 4 to 24 percent include an unknown screening history and [9,10]:

●HPV positive with atypical squamous cells of undetermined significance (ASC-US; risk of CIN 3+ 4.4 percent).

●HPV positive with low-grade squamous intraepithelial lesion (LSIL; risk of CIN 3+ 4.3 percent).

●HPV negative with ASC-H (risk of CIN 3+ 3.4 percent).

●HPV genotype 16 and 18 positive with negative cytology.

Colposcopic-guided biopsies will provide information to help guide clinical decision-making (eg, treatment with excision or ablation versus follow with observation) and are discussed in detail separately. (See "Cervical intraepithelial neoplasia: Management".)

Surveillance: Immediate CIN 3+ risk <4 percent — Surveillance is recommended when the immediate risk of CIN 3+ is <4 percent. As discussed above, these recommendations are based on expert committee opinion with the goal of providing a reasonable balance between cancer prevention and the potential harms of overtesting and overtreatment [9]; however, not all cervical cancers can be prevented. Some providers and patients may not be comfortable with the recommended surveillance intervals described below and may opt for more frequent testing. In our practice, we focus on shared decision-making and encourage patients and providers to follow these surveillance protocols whenever possible. When appropriate, medical interpreters and cultural navigators should be included in the conversation in order to increase shared decision-making practices, reduce misunderstandings, and promote screening and management compliance.

When the immediate risk of CIN 3+ is <4 percent, the frequency of surveillance depends on the five-year risk for CIN 3+ (algorithm 1) [9,10]:

Testing in one year: Five-year risk ≥0.55 percent — When the immediate risk of CIN 3+ is <4 percent and the five-year risk is ≥0.55 percent, the patient can be followed with HPV-based testing in one year [9,10]. These patients have mild abnormalities and do not reach the threshold for evaluation with colposcopy.

Examples — Three examples of patients in whom testing can be performed in one year include:

●HPV positive with negative for intraepithelial lesion or malignancy (NILM) and an unknown history (risk of CIN 3+ at five years 4.8 percent).

●HPV positive with LSIL or less (LSIL, ASC-US, and NILM) and a prior HPV-negative screen (risk of CIN 3+ at five years 3.8, 3.8, and 2.3 percent, respectively).

●HPV-negative with LSIL and an unknown history (risk of CIN 3+ at five years 2 percent).

Testing in three years: Five-year risk 0.15 to 0.54 percent — When the immediate risk of CIN 3+ is <4 percent and the five-year risk is between 0.15 and 0.54 percent, the patient can be followed with HPV-based testing in three years.

Examples — Two examples of patients in whom testing can be performed in three years include:

●HPV negative with ASC-US and an unknown history (risk of CIN 3+ at five years 0.4 percent).

●HPV negative with ASC-US and a prior HPV-negative screen (risk of CIN 3+ at five years 0.36 percent).

Testing in five years: Five-year risk <0.15 percent — When the immediate risk of CIN 3+ is <4 percent and the five-year risk is <0.15 percent, the patient can be followed with HPV-based testing in five years.

Examples — Two examples of patients in whom testing can be performed in five years include:

●HPV negative with no cytology performed (risk of CIN 3+ at five years 0.14 percent).

●HPV negative with NILM (risk of CIN 3+ at five years 0.12 percent).

These risks are similar to the general population and, therefore, follow similar testing intervals as those described in the cervical cancer screening guidelines. (See "Screening for cervical cancer in resource-rich settings".)

MANAGEMENT OF AVERAGE-RISK PATIENTS WITH UNKNOWN RISK ESTIMATE — As stated above, management of cervical cancer screening results requires determination of a patient's immediate and five-year risks for developing CIN; this is done with the American Society for Colposcopy and Cervical Pathology (ASCCP) management guidelines application ("app"), which is available both online and for smartphones. This application allows for the provider to determine the optimal management strategy. (See 'Rationale and risk estimation' above and 'Tables and applications (calculators)' above.)

Management of screening results in patients ≥25 years at average risk (ie, not under surveillance for a prior cervical test result abnormality, no history of CIN grade 2 or worse within the past 25 years, not immunocompromised) and for whom a risk estimate has not been calculated (eg, no access to the "app") is described here [9,15].

HPV 16 or 18 positivity — Patients who are positive for HPV genotypes 16 and 18 are at an increased risk of CIN 3 and cancer. Such patients are managed as follows [9,15]:

●LSIL, ASCUS, NILM, or cytology unknown – Colposcopy. HPV 16 or 18 positivity combined with a low-grade squamous intraepithelial lesion (LSIL), atypical squamous cells of undetermined significance (ASC-US), negative for intraepithelial malignancy (NILM), or unknown cytology is an indication for immediate referral to colposcopy. (See 'Colposcopy: Immediate risk 4 to 24 percent' above.)

●HSIL – Expedited treatment. HPV 16 or 18 positivity combined with a high-grade squamous intraepithelial lesion (HSIL) is an indication for expedited treatment with an excisional procedure. (See 'Expedited treatment: Immediate risk >60 percent' above.)

HPV positive, unknown genotype or HPV 16/18 negative — Patients in whom HPV is positive, but genotyping is unknown or is negative for HPV 16/18 are managed as follows [9,15]:

●NILM – HPV testing with or without cytology in one year. (See 'Testing in one year: Five-year risk ≥0.55 percent' above.)

●ASC-US or LSIL – Colposcopy. (See 'Colposcopy: Immediate risk 4 to 24 percent' above.)

●HSIL – Expedited treatment or Colposcopy. (See 'Expedited treatment or colposcopy: Immediate risk 25 to 59 percent' above.)

HPV unknown — Patients in whom HPV is unknown are managed as follows [9,15]:

●HSIL – Expedited treatment or Colposcopy. (See 'Expedited treatment or colposcopy: Immediate risk 25 to 59 percent' above.)

●LSIL – Colposcopy. (See 'Colposcopy: Immediate risk 4 to 24 percent' above.)

●ASC-US – HPV testing with or without cytology in one year. (See 'Testing in one year: Five-year risk ≥0.55 percent' above.)

●NILM – Routine age-based screening. (See "Screening for cervical cancer in resource-rich settings", section on 'Screening in average-risk patients'.)

HPV negative — Patients in whom HPV is negative are managed as follows [9,15]:

●HSIL – Expedited treatment or Colposcopy. (See 'Expedited treatment or colposcopy: Immediate risk 25 to 59 percent' above.)

●LSIL – HPV testing with or without cytology in one year. (See 'Testing in one year: Five-year risk ≥0.55 percent' above.)

●ASC-US – HPV testing with or without cytology in three years. (See 'Testing in three years: Five-year risk 0.15 to 0.54 percent' above.)

●NILM – Routine age-based screening. (See "Screening for cervical cancer in resource-rich settings", section on 'Screening in average-risk patients'.)

SPECIAL POPULATIONS

Patients <25 years — Patients <25 years old have high spontaneous regression rates of human papillomavirus (HPV) and a relatively low risk of developing cervical cancer [9]. Therefore, an even more conservative management plan can be applied to this group given the risk of cervical intraepithelial neoplasia (CIN) 3+ is lower than in patients ≥25 years old. As such, the following recommendations apply to patients <25 years with their first abnormal cytology result (algorithm 2) [9,16]:

●For cytology results of low-grade squamous intraepithelial lesion (LSIL), atypical squamous cells of undetermined significance (ASC-US) with positive HPV, or ASC-US with unknown HPV status, repeat cytology (without HPV testing) is recommended in one and two years.

●For cytology results of ASC-US with negative HPV, repeat cytology is recommended in three years.

●Return to routine screening may begin after two consecutive negative results. (See "Screening for cervical cancer in resource-rich settings".)

If a high-grade lesion (high-grade squamous intraepithelial lesion [HSIL], atypical squamous cells cannot exclude HSIL [ASC-H], atypical glandular cells) is found at any point or if a low-grade lesion (ASC-US, LSIL) persists at the two-year follow-up, the recommendation is for colposcopy, and further management is based on biopsy results and is described in detail elsewhere. (See "Cervical intraepithelial neoplasia: Management", section on 'Management of patients <25 years'.)

Once a patient reaches the age of 25, they should be managed by the same risk-based estimates described above for patients ≥25 years old. (See 'Management based on risk estimate' above.)

Pregnant patients — Pregnancy-related physiologic and anatomic changes result in the production of more metaplastic cells, and reactive changes and inflammation make evaluation of atypical squamous cells more challenging in this population [17,18]. As an example, one study reported that ASC-H in pregnant patients had a lower positive predictive value for an underlying HSIL than in the general population [19]. In general, pregnant patients are managed in the same way as nonpregnant patients. The exceptions to this are [9]:

●Pregnant patients are not candidates for expedited treatment.

●Endocervical sampling with a curette and endometrial sampling should not be performed as there is a risk of disturbing the pregnancy; however, the endocervical canal may be sampled gently with a cytobrush.

●If colposcopy is performed, cervical biopsy should be performed only if a lesion is present that appears to be high-grade. If CIN 2+ is not diagnosed or suspected, follow-up can be performed postpartum. (See "Cervical intraepithelial neoplasia: Management", section on 'Pregnant patients'.)

We perform postpartum cytology, HPV, and colposcopic evaluation on all patients with HSIL diagnosed during pregnancy, but we defer these examinations until four weeks postdelivery to allow the cervix to resume its nonpregnant state.

Immunocompromised patients — Cervical cancer screening abnormalities (cytology or HPV testing) in immunocompromised patients are discussed in detail elsewhere [20]. (See "Screening for cervical cancer in patients with HIV infection and other immunocompromised states", section on 'Evaluation of abnormal results'.)

Patients with a history of hysterectomy — While cervical cancer screening is not routinely performed for patients who have undergone a hysterectomy for benign disease, if vaginal cytology or HPV is performed and is abnormal [9]:

●LSIL and HPV-positive ASC-US should be managed with repeat testing in one year; as with testing in patients with a cervix, vaginal HPV testing in posthysterectomy patients is thought to be superior to testing with cytology alone [21].

●ASC-H and HSIL should be managed with immediate colposcopy.

Patients with a history of CIN 2+ who have undergone hysterectomy undergo surveillance for 25 years given their increased risk for vaginal intraepithelial neoplasia. This is discussed in detail elsewhere (see "Cervical intraepithelial neoplasia: Choosing excision versus ablation, and prognosis and follow-up after treatment", section on 'Type and duration of testing'). If an abnormal squamous lesion is detected during their surveillance, they should be managed by the risk estimates described above.

Patients >65 years — Cervical cancer screening is generally discontinued at age 65 if prior screening results were normal. Screening should continue for patients >65 years with a history of abnormal screening results or a prior treatment for precancer. If testing is performed after age 65 and an abnormal squamous lesion or positive HPV result is identified, then the patient should be managed similarly to those patients age ≥25 years [9,22] (see 'Management based on risk estimate' above). Discontinuation of testing in patients with an abnormal result is only recommended in patients in poor health or with a limited life expectancy. This is discussed in detail elsewhere. (See "Screening for cervical cancer in resource-rich settings", section on 'Age >65 years'.)

Other — Some results are not addressed by the American Society for Colposcopy and Cervical Pathology (ASCCP) management guidelines application online (see 'Tables and applications (calculators)' above). Such results include:

●Patients in whom colposcopy was recommended but not performed; if repeat testing demonstrates persistent HPV positivity and/or cytologic abnormality (ASCUS or higher), colposcopy should be performed [23].

●Patient in whom two consecutive HPV tests are positive; colposcopy should be performed [23].

These recommendations are consistent with previous ASCCP guidelines [20].

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Cervical cancer screening, prevention, and management".)

INFORMATION FOR PATIENTS — UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5^th to 6^th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10^th to 12^th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.

Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)

●Basics topics (see "Patient education: Cervical cancer screening tests (The Basics)")

●Beyond the Basics topic (see "Patient education: Follow-up of low-grade abnormal Pap tests (Beyond the Basics)")

SUMMARY AND RECOMMENDATIONS

●Terminology – Screening for cervical cancer includes testing for oncogenic subtypes of human papillomavirus (HPV), cervical cytology, and co-testing with both HPV and cervical cytology. Abnormal squamous cervical cytology findings may be described as atypical squamous cells (ASC), low-grade squamous intraepithelial lesions (LSIL), or high-grade squamous intraepithelial lesions (HSIL). Further evaluation of these abnormalities is required to exclude the presence of a precancerous or cancerous condition. (See 'Introduction' above and 'Terminology' above.)

●Incidence – Atypical squamous cells of undetermined significance (ASC-US) is the most common type of squamous cell abnormality. The incidence of each type of abnormality can be found in the table (table 3). (See 'Incidence' above.)

●Risk estimation

•The risk of invasive cervical cancer is calculated using current HPV and cervical cytology results as well as past screening and clinical history, if known. Past screening history includes HPV results alone or HPV results in combination with cytology results; past cytology results alone are not used to calculate risk. (See 'Rationale and risk estimation' above.)

•Evaluation is dependent on a patient's immediate and five-year risk estimates for developing cervical intraepithelial neoplasia (CIN) 3+ (CIN 3, adenocarcinoma in situ, and cancer); once the risk estimate is determined, the patient is then assigned to one of six different management groups (algorithm 1): expedited treatment, a choice between expedited treatment and colposcopy, colposcopy, or surveillance at one-, three-, and five-year intervals. (See 'Rationale and risk estimation' above and 'Management based on risk estimate' above.)

●Management based on risk estimate using the ASCCP "app"

•Management "app" – The American Society for Colposcopy and Cervical Pathology (ASCCP) provides a management guidelines application ("app"), both online and for smartphones, to determine a patient's immediate and five-year risks for developing cervical intraepithelial neoplasia (CIN) 3+. Use of this application allows for the provider to determine the optimal management strategy. (See 'Tables and applications (calculators)' above.)

•Expedited treatment (immediate risk: >60 percent) – For most nonpregnant patients ≥25 years of age in whom the immediate CIN 3+ risk is >60 percent, we suggest expedited treatment with excision (usually in the form of loop electrosurgical excision procedure [LEEP]) rather than deferring treatment until after further diagnostic evaluation with colposcopy (Grade 2C). Typically, these patients require treatment, and colposcopy is unlikely to alter this management. Treatment, however, is associated with potential adverse pregnancy outcomes (eg, preterm delivery); therefore, patients planning future childbearing may reasonably choose colposcopy rather than expedited treatment to minimize these risks if an excisional procedure can be avoided based on colposcopic biopsy results. (See 'Expedited treatment: Immediate risk >60 percent' above and 'Exceptions' above.)

•Expedited treatment or colposcopy (immediate risk: 25 to 59 percent) – For most nonpregnant patients ≥25 years of age in whom the immediate CIN 3+ risk is 25 to 59 percent, expedited treatment or colposcopy are acceptable options. Expedited treatment may be preferred in those patients who are at risk for loss to follow-up or who have completed childbearing and are not concerned about the potential adverse pregnancy outcomes associated with treatment. (See 'Expedited treatment or colposcopy: Immediate risk 25 to 59 percent' above and 'How to choose' above.)

•Colposcopy (immediate risk: 4 to 24 percent) – For most nonpregnant patients ≥25 years of age in whom the immediate CIN 3+ risk is 4 to 24 percent, we proceed with diagnostic evaluation with colposcopy to guide decisions regarding management. Treatment with excision or ablation may be avoided in some patients, and colposcopic biopsies will provide information to help guide clinical decision-making. (See 'Colposcopy: Immediate risk 4 to 24 percent' above.)

•Surveillance (immediate risk: <4 percent) –For most nonpregnant patients ≥25 years of age in whom the immediate CIN 3+ risk is <4 percent, long-term surveillance with HPV-based testing is required. These patients have mild abnormalities and do not reach the threshold for evaluation with colposcopy. The frequency of surveillance depends on the five-year risk for CIN 3+ and is detailed in the algorithm (algorithm 1). (See 'Surveillance: Immediate CIN 3+ risk <4 percent' above.)

●Management without using the "app" – Management of patients ≥25 years at average risk (ie, not under surveillance for a prior cervical test result abnormality, no history of CIN grade 2 or worse within the past 25 years, not immunocompromised) for whom a risk estimate has not been calculated (eg, no access to the management "app") is based on their HPV and cytology results. (See 'Management of average-risk patients with unknown risk estimate' above.)

●Special populations

•Patients <25 years – Patients <25 years old have high spontaneous regression rates of HPV and a relatively low risk of developing cervical cancer as they are among the cohort of patients targeted to receive the HPV vaccine. Therefore, an even more conservative management approach can be applied to this group given that the risk of CIN 3+ is lower than in patients ≥25 years old. (See 'Patients <25 years' above.)

•Pregnant patients – Pregnant patients are managed similarly to nonpregnant patients with a few major differences: They are not candidates for expedited treatment or endocervical curettage (but gentle sampling of the endocervical canal with a cytobrush may be performed) and in patients undergoing colposcopy, a biopsy should only be performed if cancer is suspected. In our practice, we perform cytology, HPV, and colposcopic evaluation but generally defer these examinations until four weeks postdelivery. (See 'Pregnant patients' above.)

•Immunocompromised patients – The management of immunocompromised patients with cervical cytology abnormalities is discussed in detail elsewhere. (See 'Immunocompromised patients' above.)